Fountain-pen



K. MATSUMOTO AND K. TAKAGI.

FOUNTAIN PEN.

APPLICAT ON FlL E D IULY 7. 1920.

Patented May 31, 1921. FIG IsHEEIs-sHEET I.

awrlrollllf K. MATSUMOTO AND K. TAKAGI.

FOUNTAIN PEN.

APPLICATION FILED |ULY7.1920.

1,380,233 1 Pat nted May 31. 1921.

2 SHEETS-SHEET 2 UNITED STATES PATENT OFFICE.

FOUNTAIN-PEN.

Specification of Letters Patent.

Patented May 31, 1921.

Application filed July 7, 1920. Serial No. 394,468.

To all whom it may concern:

Be it known that KEN MATSUMOTO and KIsAB no TAKAcr, subjects of the Emperor of Japan, both rcslding at No. 14. Komagome Shinmei-cho, Hongo-ku, Tokyo, Japan, have invented certain new and useful Improvements in Fountain-Pens, of which the following is a specification.

This invention relates to improvements in a fountain pen comprising an ink holder provided with screw threads at external and internal surfaces of open end of the barrel thereof, a cap provided with internal screw thread to be engaged with said external thread of the barrel and a center screw pin provided with externally screw threaded point at the free end thereof, and a point section provided with external screw thread to be engaged with the internal screw thread of the said barrel and internally .screw threaded hole to be engaged with the screw threaded point of the said center screw pin.

The object of the invention is to obtain an improved form of fountain pen which is simple and strong in construction, has greater volume of ink holder and perfectly prevents drying of ink in pen when not in use.

In the drawings. v

Figure 1 is a longitudinal sectional View of a fountain pen according to this in vention, showing when the cap is disengaged with the rest part; Fig. 2 is the same sectional view when the cap is about being applied to the barrel; Fig. 3 shows the same view when the cap is midway on the barrel and filling the ink; Fig. 4 shows the same sectional view when the cap is fully applied to the barrel; Fig. 5 shows the fountain pen when in use with a small reserve of ink in the barrel and Fig. 6 shows several views of the point section.

In the drawings, A is an ink holder, B is a cap and G is a point section of the fountain pen. The part A consists of a barrel 1 and a plug 6, the barrel being provided with internal thread 1' and external thread 1 in its open end. The part B consists of a tube 3 and a head 3. The tube 3 is provided with a hole 7 for filling ink and internal thread 3".

The head 3' is screwed into the said tube and to which a center screw pin 4 is rigidly fitted. The head 3' can be detachable from the tube 3 together with the center screw pin for cleaning or otherwise where necesfew times. Then the screw point 4 of the center screw pin 4 engages into the internally screwed hole 2" of the point section, so that the position of the parts comes from that of Fig. l to that of Fig. 2 by further turning the cap a few times more in the same direction the point section 2 is disengaged from the internal screw 1' of the barrel carried by the said center screw pin. Therefore by pushing the cap toward the barrel, the point section can be easily dipped into the ink chamber in the barrel, so that the parts come into such a position as shown in F 1g. 3. The ink may be filled froin the hole 7 by means of commonly known ink supplier, if necessary, in this position of the cap in relation to the barrel. When the cap is further pushed toward the barrel, the

internal screw (3") is engaged to the ex-' ternal screw (1) of the barrel. Therefore by turning the cap in the same direction a few times the parts come into a position as shown in Fig. 4. In this position of the cap in relation to the barrel, the inner base of the head 3 abuts tightly to the opened end of the barrel so that the ink can be perfectly stopped without any leakage from the point sectlon.

When one wishes to use the fountain pen the operation described in the preceding paragraph is executed inversely. Therefore, when the cap is turned a few times in the opposite direction to the former operation, the parts can come out in position from that as shown in Fig. 3 to that as shown in Fig. 4. By a further turning of the cap, the point section 2 can be brought up until it is engaged with the internal screw of the barrel. By a further turning of the cap in continued direction, the center screw pm is disengaged from the point section, leaving the section in tightly engaged position with the iipternal screw of the barrel as shown in '2. 1.

The cap may then be applied to the rear end of the plug 6, ready for use as usual type. The cap must be applied to or disenga d from the barrel a ways in upright position of the fountain pen. Briefly when one wishes to retire the pen after use it is only necessary to turn the cap in one direction, or conveniently in clockwise direction, and otherwise or for use it is sufiicient to turn the cap in the opposite direction.

Considering the feed of ink from ink chamber to the pen according to this invention, one can find out a very delicate action of ink. As the ink filled in the barrel gradually decreases, the pressure of space A or ink chamber is reduced and there is created a partial vacuum in this space.

Therefore the ink leaks out verly slowly and does not run out in excess from the pen, moreover, even for the final small quantity of ink, the pass of the ink is suitably hindered by zigzag surface of the internal screw; facing to the ink passage 2 as shown in Fig. 2. Therefore even when the partial vacuum is not created in the space A for the final quantity of the ink, it can only slowly leak out from the pen and does never run out suddenly as frequently to be seen in hitherto known types of the fountain pen.

The pen 5 in this invention is always dipped into the ink, or otherwise covered air tightly by the barrel. Therefore when it is brought out or protruded from the barrel, it is always wetted ready for writing, and there is no chance of crusting the dried ink on the pen. Therefore there is no necessity of shaking or coaxing the pen for use and one can always use the pen only by disengaging the cap from the barrel.

Shortly as there is no special apparatus in the pen except that for retiring or protruding the pen holder, the construction of the improved fountain pen is very simple and strong and the volume of the ink chamber becomes greater in given length of the barrel. The even part of the improved. fountain pen can be very easily detached from each other and rapidly decomposed.

Therefore the cleaning of the ink barrel, rcpairing or interchange of any damaged part are very simply attained in very short time, thus saving cost and time therefor, moreover the treatment of the improved pen is very simple, a few turns of one direction or other are all that is necessary operation for ready for or after use of the fountain pen.

Claims:

1. A fountain pen including a barrel provided at its open end with external screwthreads, a pen holder in threaded engagement with the open end of said barrel, and provided with an internal thread, a cap provided near its closed end with internal screw threads designed to engage the external threads at the open end of the barrel, and a stem carried by the cap and provided at its free end with external threads designed to engage the internal threads of the pen holder for attaching and detaching said pen holder to and from the barrel, said cap being designed to close the open end of said barrel when the internal threads of the cap are in tight engagement with the external threads of the barrel, said cap being provided with a side opening through its wall to' permit the barrel to be filled with ink after the stem has detached the penholder from the barrel.

2. A fountain-pen including a barrel having an open end provided with internal threads, a pen-holder provided with external threads to engage the internal threads of the barrel, and a pen carried by the penholder, said pen-holder being provided with an ink-passageway, a longitudinal groove cut in the external surface of the pen-holder and having its mouth closed by the internal threaded portion of the barrel whereby ink passing through said groove to said passageway will be retarded by the internal threads.

In testimony whereof they aflix their signatures in the presence of two witnesses.

KEN MATSUMOTO. [L. 8.] KISABURO TAKAGI. [L. s.] Witnesses: I

GENJI KUNBARA, C. ARoILLAs. 

